21222451255 has 4 divisors (see below), whose sum is σ = 25466941512. Its totient is φ = 16977961000.

The previous prime is 21222451247. The next prime is 21222451267. The reversal of 21222451255 is 55215422212.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21222451255 - 2³ = 21222451247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2122245121 + ... + 2122245130.

It is an arithmetic number, because the mean of its divisors is an integer number (6366735378).

Almost surely, 2^21222451255 is an apocalyptic number.

21222451255 is a deficient number, since it is larger than the sum of its proper divisors (4244490257).

21222451255 is an equidigital number, since it uses as much as digits as its factorization.

21222451255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4244490256.

The product of its digits is 16000, while the sum is 31.

Adding to 21222451255 its reverse (55215422212), we get a palindrome (76437873467).

The spelling of 21222451255 in words is "twenty-one billion, two hundred twenty-two million, four hundred fifty-one thousand, two hundred fifty-five".